To understand how the nervous system operates it is important to study structure, function and formation of the synapse. One of the most important structure at the synapse is the site of transmitter release: the active zone. In this proposal the induction of the active zoe at ectopic endplate sites in the frog will be studied with intracellular recording and freeze-fracture electron microscopy. Ectopic junctions will be induced de novo by removing the original endplate zone and implanting original nerves to endplate-free areas. Whether or not the active zone is formed at the ectopic junction will be examined, especially in relation to the postjunctional fold if the latter is also formed. The result will be compared with a previous study on regeneration of the active zone at the original endplate. In addition the morphometry of active zones at ectopic junctions will be analyzed to study if it correlates with the increase in transmitter release shown with intracellular recording. The proposed research will elucidate how the unique organization of the active zone is induced and differentiated. It will also provide a better understanding on correlation between active zone structures and transmitter released efficacy. This basic knowledge on how synapses form and work would throw light on understanding the mechanisms of certain neurological diseases which may involve deficiency in transmitter release.